Silk fibroin(SF)/fucoidan blend films with different blend ratios were prepared by mixing aqueous solutions of SF and fucoidan The structural characteristics and thermal properties were examined through Fourier transform infrared (FTIR) spectroscopy

X-ray diffractometry (XRD)

thermogravimetry

and differential scanning calorimetry (DSC) The conformation of SF in blend films was revealed to be a β-sheet structure

according to the results of FTIR and XRD spectra This result was also confirmed through DSC thermograms

the exotherm at around 230℃．that was attributed to the random coil conformation of SF．was not observed in blend films．These results demonstrated that the conformation change of SF occurred from a random coll to a β-sheet structure due to the formation of intermolecular hydrogen bonds between fucoidan and SF in the blend films．The crystalline SF films showed higher thermal stability than the amorphous SF film．